The overall aim of this project is to develop a method of cancer radioimmunodetection for prostatic cancer. Radioimmunodetection involves the administration of radioactive antibodies to tumor-specific or -associated antigens and the use of totalbody scintigraphy to visualize areas of increased radioactivity presumably reflecting sites of tumor. The prostatic cancer-associated substances to serve as targets for radioimmunodetection will be prostatic acid phosphatase (PAP) and carcinoembryonic antigen (CEA). As more specific prostatic cancer antigens become identified in the future, these will likewise be evaluated as targets for radioimmunodetection. In addition to goat antibodies against PAP and CEA, hybridoma monoclonal antibodies will be generated and evaluated. Since bone represents a major site of metastasis for prostatic cancer, antibody fragments to PAP and CEA will be compared to the bone localizing efficacy of whole IgG preparations. In order to aid in preoperative staging of prostatic cancer, a method of radioimmunodetection lymphoscintigraphy will be developed and tested, involving either injection of PAP and CEA antibodies directly into the prostate or into the anal sphincter muscle for lymphatic visualization, including the obturator nodes.